Database Zones

2006-09-16T03:12:00.002-07:00

Oracle

An Oracle database consists of a collection of data managed by an Oracle database management system. Popular generic usage also uses the term to refer to the Oracle DBMS management software, but not necessarily to a specific database under its control.

One can refer to the Oracle database management system unambiguously as Oracle DBMS or (since it manages databases which have relational characteristics) as Oracle RDBMS.
An Oracle database comprises an instance and data storage. The instance comprises a set of operating system processes and memory structures that interact with the storage. Typical processes include PMON (the process monitor) and SMON (the system monitor).

Oracle users refer to the server-side memory-structure as the SGA (System Global Area). The SGA typically holds cache information like data-buffers, SQL commands and user information. In addition to storage, the database consists of online redo logs (which hold transactional history). Processes can in turn archive the online redo logs into archive logs (offline redo logs), which provide the basis (if necessary) for data recovery and for some forms of data replication.

The Oracle RDBMS stores data logically in the form of tablespaces and physically in the form of data files. Tablespaces can contain various types of segments, for example, Data Segments, Index Segments etc. Segments in turn comprise one or more extents. Extents comprise groups of contiguous data blocks. Data blocks form the basic units of data storage. At the physical level, data files comprise one or more data blocks, where the blocksize can vary.

Oracle Corporation itself blurs the very useful distinction between:

1. data managed by an Oracle RDBMS
2. an Oracle database, and
3. the Oracle RDBMS software itself

when it refers nowadays to the Oracle RDBMS (the software it sells for the purpose of managing databases) as the Oracle Database. The distinction between the managed data (the database) and the software which manages the data (the DBMS / RDBMS) relies, in Oracle's marketing literature, on the capitalisation of the word database.

Oracle Corporation produces and markets the Oracle DBMS, which many database applications use extensively on many popular computing platforms.

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2006-09-16T03:12:00.001-07:00

MY SQL

MySQL is a multithreaded, multi-user, SQL Database Management System (DBMS) with more than six million installations.[1] MySQL AB makes MySQL available as free software under the GNU General Public License (GPL), but they also dual-license it under traditional proprietary licensing arrangements for cases where the intended use is incompatible with the GPL.

MySQL is owned and sponsored by a single for-profit firm, the Swedish company MySQL AB, which holds the copyright to most of the codebase. This is similar to the JBoss model and how the Free Software Foundation handles copyright in its projects, and dissimilar to how the Apache project does it, where the software is developed by a public community, and the copyright to the codebase is owned by its individual authors.

The company develops and maintains the system, selling support and service contracts, as well as proprietary-licensed copies of MySQL, and employing people all over the world who collaborate via the Internet. MySQL AB was founded by David Axmark, Allan Larsson, and Michael "Monty" Widenius.

The MySQL company also sells another DBMS, MaxDB, which is from an unrelated codebase.

MySQL is popular for web applications such as MediaWiki or Drupal and acts as the database component of the LAMP, MAMP and WAMP platforms (Linux/Mac/Windows-Apache-MySQL-PHP/Perl/Python), and for open-source bug tracking tools like Bugzilla. Its popularity as a web application is closely tied to the popularity of PHP, which is often combined with MySQL and nicknamed the Dynamic Duo. It is easy to find many references that combine the two in websites and books (PHP and MySQL for Dummies, PHP and MySQL Bible, Beginning PHP and MySQL, etc.) The claim made in many books is that MySQL is easier to learn and use than many other database applications. An example from the Dummies book is that you can quit MySQL with an obvious command of either exit or quit, although this is true for many other database applications.

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2006-09-16T03:12:00.000-07:00

SQL

SQL (commonly expanded to Structured Query Language — see History for the term's derivation) is the most popular computer language used to create, modify, retrieve and manipulate data from relational database management systems. The language has evolved beyond its original purpose to support object-relational database management systems. It is an ANSI/ISO standard.

SQL is commonly spoken in initialism-style ess-cue-el (see English alphabet) — regarded as more formal — or in a phonetically amalgamated form that mirrors the English word sequel. Concerning the names of major database products (or projects) containing the letters SQL, each has its own convention: MySQL is officially and commonly pronounced "My Ess Cue El"; PostgreSQL is expediently pronounced postgres; and Microsoft SQL Server is commonly spoken as Microsoft-sequel-server.

The first non-commercial, relational, non-SQL database, Ingres, was developed in 1974 at U.C. Berkeley.

In 1978, methodical testing commenced at customer test sites. Demonstrating both the usefulness and practicality of the system, this testing proved to be a success for IBM. As a result, IBM began to develop commercial products based on their System R prototype that implemented SQL, including the System/38 (announced in 1978 and commercially available in August 1979), SQL/DS (introduced in 1981), and DB2 (in 1983).[1]

At the same time Relational Software, Inc. (now Oracle Corporation) saw the potential of the concepts described by Chamberlin and Boyce and developed their own version of a RDBMS for the Navy, CIA and others. In the summer of 1979 Relational Software, Inc. introduced Oracle V2 (Version2) for VAX computers as the first commercially available implementation of SQL. Oracle is often incorrectly cited as beating IBM to market by two years, when in fact they only beat IBM's release of the System/38 by a few weeks. Considerable public interest then developed; soon many other vendors developed versions, and Oracle's future was ensured.

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2006-09-16T03:11:00.000-07:00

DATABASE MAIN

In this zone, you will find the Ebooks on all well known Databases such as Oracle, SQL and MY SQL. This section is purely dedicated towards providing Latest source of Ebooks on the various aspects of the database development and programming. This will surely help the newbie or advanced programmer on the usage of the databases. Also, Please post your request in Suggestion/Comments/Request Box so that we can post the material requested by you as soon as possible so that this section can serve you in better manner.

Database Zones

Oracle SQL MY SQL